Conveyor carriage position monitoring

ABSTRACT

A carriage system including a carriage having a target; a winch; a position sensor configured to sense a position of the target; and a controller. The winch includes a cable, a motor, and a motor sensor. The cable couples the carriage to the winch. The motor sensor senses a motor characteristic. The controller is configured to receive the motor characteristic and the position of the target, calculate a characteristic of the system, and output the characteristic.

RELATED APPLICATIONS

The present application claims priority to U.S. Provisional ApplicationNo. 61/818,327, filed May 1, 2013, and U.S. patent application Ser. No.14/267,332, filed May 1, 2014, the entire contents of which are herebyincorporated.

BACKGROUND

The present invention relates to position monitoring for conveyor beltsused in the mining industry.

Position monitoring for conveyor belts is typically performed usingincremental end coders that count turns of a motor shaft of the winch.The turns of the motor shaft provide an estimated position of a conveyorcarriage, and thus an estimated length of conveyor belt in a beltstorage unit (i.e., take-up unit). However, the use of incremental endcoders is inaccurate and must be reset every time a power outage occurs.

SUMMARY

In one embodiment, the invention provides a carriage system including acarriage having a target; a winch; a position sensor configured to sensea position of the target; and a controller. The winch includes a cable,a motor, and a motor sensor. The cable couples the carriage to thewinch. The motor sensor senses a motor characteristic. The controller isconfigured to receive the motor characteristic and the position of thetarget, calculate a characteristic of the system, and output thecharacteristic.

In another embodiment, the invention provides a method of monitoring acarriage system. The carriage system includes a carriage configured tomove along the track between the proximal end and the distal end; awinch having a cable coupled to the carriage; a motor; and a positionsensor. The method includes receiving a position of the carriage;receiving a rotational speed and a rotational direction of the motor;calculating a characteristic of the carriage system; and outputting thecharacteristic of the carriage system. The characteristic is based onthe position of the carriage, the rotational speed of the motor, and therotational direction of the motor.

Other aspects of the invention will become apparent by consideration ofthe detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a side view of a conveyor system.

FIG. 2 illustrates a top view of the conveyor system of FIG. 1.

FIG. 3 illustrates a control system of the conveyor system shown inFIGS. 1 and 2.

FIG. 4 is a flowchart illustrating operation of the conveyor systemshown in FIGS. 1 and 2.

FIG. 5 illustrates a user-interface of the conveyor system of FIG. 1.

DETAILED DESCRIPTION

Before any embodiments of the invention are explained in detail, it isto be understood that the invention is not limited in its application tothe details of construction and the arrangement of components set forthin the following description or illustrated in the following drawings.The invention is capable of other embodiments and of being practiced orof being carried out in various ways. Also, it is to be understood thatthe phraseology and terminology used herein is for the purpose ofdescription and should not be regarded as limiting. The use of“including,” “comprising” or “having” and variations thereof herein ismeant to encompass the items listed thereafter and equivalents thereofas well as additional items. The terms “mounted,” “connected” and“coupled” are used broadly and encompass both direct and indirectmounting, connecting and coupling. Further, “connected” and “coupled”are not restricted to physical or mechanical connections or couplings,and can include electrical connections or couplings, whether direct orindirect. Also, electronic communications and notifications may beperformed using any known means including direct connections, wirelessconnections, etc.

It should also be noted that a plurality of hardware and software baseddevices, as well as a plurality of different structural components maybe used to implement the invention. In addition, it should be understoodthat embodiments of the invention may include hardware, software, andelectronic components or modules that, for purposes of discussion, maybe illustrated and described as if the majority of the components wereimplemented solely in hardware. However, one of ordinary skill in theart, and based on a reading of this detailed description, wouldrecognize that, in at least one embodiment, the electronic based aspectsof the invention may be implemented in software (e.g., stored onnon-transitory computer-readable medium) executable by one or moreprocessors. As such, it should be noted that a plurality of hardware andsoftware based devices, as well as a plurality of different structuralcomponents may be utilized to implement the invention. Furthermore, andas described in subsequent paragraphs, the specific mechanicalconfigurations illustrated in the drawings are intended to exemplifyembodiments of the invention and that other alternative mechanicalconfigurations are possible. For example, “controllers” described in thespecification can include standard processing components, such as one ormore processors, one or more computer-readable medium modules, one ormore input/output interfaces, and various connections (e.g., a systembus) connecting the components.

FIGS. 1 and 2 illustrate a conveyor system 100. In one embodiment, theconveyor system 100 is used in underground mining operations. In someembodiments, the conveyor system 100 is used in conjunction withlongwall mining. The conveyor system 100 transports mined material(e.g., coal, ore, rock, etc.), via a conveyor belt 105, through a mine.During transportation of the mined material, the conveyor belt 105 mustmaintain a constant proper tension.

The conveyor system 100 includes a conveyor rail system 110, a conveyorcarriage system 115, and a winch system 120. The conveyor rail system110, the conveyor carriage system 115, and the winch system 120 helpmaintain the conveyor belt 105 at a proper tension.

The conveyor rail system 110 extends along a wall of the mine. Theconveyor rail system 110 includes a proximal end 200, a distal end (notshown), a conveyor take-up 205, and rail tracks 210. The conveyortake-up 205 collects excess conveyor belt 105. The conveyor take-up 205further allows excess conveyor belt 105 out. In some embodiments, theconveyor take-up 205 includes a plurality of take-up pulleys. In such anembodiment, the conveyor belt 105 is lapped around the plurality oftake-up pulleys. In the illustrated embodiment, the conveyor take-up 205is a horizontal take-up. In another embodiment, the conveyor take-up 205is a gravity take-up. In yet another embodiment, the conveyor take-up205 is a vertical take-up. The rail tracks 210 provide a track for theconveyor carriage system 115.

In one embodiment, the conveyor carriage system 115 includes carriagewheels 250, a carriage base 255, and a drive sprocket 260. The carriagewheels 250 support the carriage base 255, and are operable to allowmovement of the conveyor carriage system 115 along the rail tracks 210.The drive sprocket 260 is connected to the carriage base 255. The drivesprocket 260 is coupled to a drive sprocket motor (not shown). The drivesprocket motor rotates the drive sprocket 260. As the drive sprocket 260is rotated, the conveyor belt 105 is driven in a desired direction fortransporting the mined material.

In another embodiment, rather than the drive sprocket 260, the conveyorcarriage system 115 includes an idler, or idle pulley. In such anembodiment, the idler in is contact with the conveyor belt 105. Theidler freely rotates as the conveyor belt 105 is driven.

The winch system 120 is located adjacent to the proximal end 200 of theconveyor rail system 110. The winch system 120 maintains a constantconnection with the carriage base 205 via a carriage cable 300. Thewinch system 120 includes a winch base 305, a winch 310, and a winchmotor 315. The winch base 305 supports the winch 310 and winch motor315. The carriage cable 300 is let-out or wound-up, by the winch 310.

During operation, the winch 310 winds-up the carriage cable 300. As thecarriage cable 300 is wound-up, the conveyor carriage system 115 movesin a first direction 350, toward the winch system 120. As the conveyorcarriage system 115 moves in the first direction 350, excess conveyorbelt 105 is stored in the conveyor belt take-up 205, resulting ingreater tension of the conveyor belt 105.

When less tension of the conveyor belt 105 is needed, the winch 310lets-out the carriage cable 300. As the carriage cable 300 is let-out,the conveyor carriage system 115 is allowed to move in a seconddirection 355, away from the winch system 120. As the conveyor carriagesystem 115 moves in the second direction 355, conveyor belt 105 is letout of the conveyor belt take-up 205.

FIG. 3 illustrates a monitoring system 400 for monitoring variousaspects of the mining system 100. The monitoring system 400 includes acontroller 405, a user-interface 410, a position sensor 415, and a winchmotor sensor 420. In other embodiments, the monitoring system 400includes more or less components. The controller 405 includes aprocessor 425 and a memory 430. The memory 430 stores instructionsexecutable by the processor 425 and various inputs/outputs for, e.g.,allowing communication between the controller 405 and the operator orbetween the controller 405 and the various sensors. In some instances,the controller 405 includes one or more of a microprocessor, digitalsignal processor (DSP), field programmable gate array (FPGA),application specific integrated circuit (ASIC), or the like.

The user-interface 410, such as an operator user-interface, providesinformation to the operator (e.g., the status of the mining system 100,characteristics of the mining system 100, etc.). The user-interface 410includes one or more of the following: a display (e.g., a liquid crystaldisplay (LCD)); one or more light emitting diodes (LEDs) or otherillumination devices; a heads-up display; speakers for audible feedback(e.g., beeps, spoken messages, etc.); tactile feedback devices such asvibration devices; or another feedback device.

The controller 405 is in communication with the position sensor 415. Insome embodiments, the position sensor 415 is an ultrasonic sensor, suchas but not limited to, a DME4000 Distance Measuring Sensor by RockwellCollins. The position sensor 415 continually senses a distance betweenthe conveyor carriage system 115 and the winch system 120. In someembodiments, the position sensor 415 is located on the winch base 305 ofthe winch system 120. The position sensor 415 acts as both an output andan input for a signal 435 (FIGS. 1 and 2). In some embodiments, thesignal 435 is an ultrasonic signal (e.g., a laser signal). The signal435 is reflected off of a target 440 located on the conveyor carriagesystem 115 (e.g., the conveyor base 225). In some embodiments, thetarget 440 is a minimum of six inches by six inches. The travel time ofthe signal 435 reflected off of the target 440 is used to determine adistance between the position sensor 415 and the target 440. Thisdistance between the position sensor 415 and the target 440 is directlyrelated to the distance between the winch system 120 and the conveyorcarriage system 115.

In operation, the position sensor 415 outputs the signal 435 towards thetarget 440. The signal 435 is reflected off of the target 440 backtowards the position sensor 415. The position sensor 415 receives thereflected signal 435. The position sensor 415 calculates the travel timeof the signal 435 travelling to the target 440, reflecting off thetarget 440, and travelling back to the position sensor 415. The positionsensor 415 calculates the distance (i.e., position of the target 440) byusing the relationship with time: Distance=½ (Speed×Time), where speedis equal to the speed of light (i.e., 300,000 km/s). The position sensor415 sends the calculated distance (i.e., position) to the controller405.

The controller 405 determines the travelling speed (i.e., velocity) ofthe conveyor carriage system 115, and the direction of the movement, asthe conveyor carriage system 115 moves toward or away from the winchsystem 120. The controller 405 determines the travelling speed from twoor more calculated distances received from the position sensor 415,along with difference in time between the calculated distances. Thetravelling speed is calculated using the following equation:Speed=(Distance₂−Distance₁)/(Time₂−Time₁).

The controller 405 is in further communication with the winch motorsensor 420. The winch motor sensor 420 monitors characteristics of thewinch motor 315, such as but not limited to, the rotational speed of thewinch motor 315 and the rotational direction of the winch motor 315. Insome embodiments the winch motor sensor 420 is a magnetic sensor (e.g.,a hall effect sensor). In other embodiments, the winch motor sensor 420is a current sensor, an optical sensor, or another type of motor sensor.The winch motor sensor 420 outputs the sensed rotational speed and thesensed rotational direction of the winch motor 315 to the controller405.

In operation, the controller 405 calculates characteristics of themining system 100 based on the position of the target 440 and/or thecharacteristics of the winch motor 315. The characteristics of themining system 100 may include, but are not limited to, operational andmechanical issues of the conveyor system 100. For example, but notlimited to, the controller 405 is operable to detect if the conveyorbelt 105 breaks, detect if the carriage cable 300 breaks, and monitor ifthere are control problems over the mining system 100.

FIG. 4 illustrates an operation 500 for determining a mechanical issueof the conveyor system 100. The controller 405 receives the rotationalspeed of the winch motor 315 from the winch motor sensor 420 (Step 505).The controller 405 calculates the travelling speed of the conveyorcarriage system 115 from the received positions of the conveyor carriagesystem 115 (Step 510). The controller 405 determines if the rotationalspeed has reached a predefined maximum rotational speed (Step 515). Ifthe rotational speed has not reached the predefined maximum rotationalspeed, the operation continues to Step 505. If the rotational speed hasreached the predefined maximum rotational speed, the controller 405determines if the travelling speed has reached a predefined maximumtravelling speed (Step 520). If the travelling speed has not reached thepredefined maximum travelling speed, the operation continues to Step505. If the travelling speed has reached the predefined maximumtravelling speed, the controller 405 determines if the rotation of thewinch motor 315 and the travelling direction of the conveyor system 110are in the same direction (Step 525). If the movement of the winch motor315 and the movement of the conveyor carriage system 115 are in the samedirection, the controller 405 determines that the conveyor belt 105 hasbroken (Step 530). If the movement of the winch motor 315 and themovement of the conveyor carriage system 115 are not in the samedirection, the controller 405 determines that the carriage cable 300 hasbroken (Step 535).

In one embodiment, if the controller 405 determines that there has beenan operational or mechanical issue with the conveyor system 100 orabnormal operation of the conveyor system 100, the controller 405 shutsdown the conveyor system 100. In another embodiment, if the controller405 determines that there has been an operational or mechanical issuewith the conveyor system 100, the controller 405 outputs an alert to anoperator via the user-interface 410. An operational or mechanical issuemay include, but is not limited to, a broken conveyor belt 105, a brokencarriage cable 300, a misalignment of the position sensor 415, amisalignment of the target 440, an over-speed condition of the winch 310(e.g., during pay-in operations or pay-out operations), encoder speederrors, and abnormal operation of the conveyor system 100 (e.g.,abnormal operation of the winch 310, unstable conveyor belt 105, etc.).In some embodiments the controller 405 determines if there has beenabnormal operation of the conveyor system 100 by comparing real-timevelocity values of the winch motor 315 and/or the conveyor carriagesystem 115 with standard velocity models. Variations between thereal-time velocities and the standard velocity models may indicate anabnormal operation of the conveyor system 100. For example, if aconveyor belt 105 is unstable, the conveyor belt 105 producesoscillations. These oscillations can be detected by the controller 405by analyzing variations between the real-time velocities and thestandard velocity models.

FIG. 5 illustrates an embodiment of user-interface 410. In theillustrated embodiment, the controller 405 outputs a plurality ofcharacteristics 600 of the conveyor system 100. The plurality ofcharacteristics 600 may include, but are not limited to, a capacity oftake-up 605, a velocity 610 of the conveyor carriage system 115, anamount 615 of the conveyor belt 105 remaining in the conveyor take-up205, and a distance 620 that the conveyor carriage system 115 willtravel before the conveyor take-up 205 is full.

In another embodiment, the controller 405 is further in communication(e.g., wired communication or wireless communication) with a network. Insuch an embodiment, the controller 405 outputs the characteristics ofthe mining system 100 to the network for further analysis.

Thus, the invention provides, among other things, position monitoringfor conveyor belts used in the mining industry. Although the inventionhas been described in detail with reference to certain preferredembodiments, variations and modifications exist within the scope andspirit of one or more independent aspects of the invention as described.

What is claimed is:
 1. A carriage system comprising: a carriageincluding a target; a winch including a cable coupling the carriage tothe winch, a motor, and a motor sensor configured to sense a motorcharacteristic; a position sensor configured to sense a position of thetarget; and a controller having a memory and a processor, the controllerconfigured to receive the motor characteristic and the position of thetarget, calculate a characteristic of the system, and output thecharacteristic.
 2. The carriage system of claim 1, wherein the motorsensor is at least one selected from the group consisting of a magneticsensor, a current sensor, and an optical sensor.
 3. The carriage systemof claim 1, wherein the position sensor is an ultrasonic sensor.
 4. Thecarriage system of claim 1, wherein the motor characteristic includes atleast one selected from the group consisting of a rotational speed and arotational direction.
 5. The carriage system of claim 1, wherein theposition is a distance between the target and the position sensor. 6.The carriage system of claim 1, wherein the characteristic is output toat least one selected from the group consisting of a user-interface anda network.
 7. The carriage system of claim 1, wherein the characteristicis a velocity of the carriage.
 8. The carriage system of claim 1,wherein the controller further determines if the cable is broken basedon a rotational direction of the motor and a direction of movement ofthe carriage being opposite.
 9. The carriage system of claim 1, whereinthe controller is further configured to determine if an issue is presentand shut down the carriage system if an issue is present.
 10. Thecarriage system of claim 1, further comprising a conveyor belt; and aconveyor take-up for collecting excess conveyor belt.
 11. The carriagesystem of claim 10, wherein the characteristic is a capacity of theconveyor take-up.
 12. The carriage system of claim 10, wherein thecharacteristic is a length of the conveyor belt in the conveyor take-up.13. The carriage system of claim 10, wherein the controller furtherdetermines if the conveyor belt is broken based on a rotationaldirection of the motor and a direction of movement of the conveyorcarriage being equal.
 14. The carriage system of claim 1, wherein thecarriage further includes a base rotatably supporting a conveyor belt.15. A method of monitoring a carriage system including a carriageconfigured to move along the track between the proximal end and thedistal end, a winch having a cable coupled to the carriage, a motor, anda position sensor, the method comprising: receiving a position of thecarriage; receiving a rotational speed and a rotational direction of themotor; calculating a characteristic of the carriage system, thecharacteristic based on the position of the carriage, the rotationalspeed of the motor, and the rotational direction of the motor; andoutputting the characteristic of the carriage system.
 16. The method ofclaim 15, wherein the characteristic is a velocity of the carriage. 17.The method of claim 15, further comprising determining if the cable isbroken based on the rotational direction of the motor and a direction ofmovement of the carriage being opposite.
 18. The method of claim 15,wherein the characteristic is a length of a conveyor belt in a conveyortake-up.
 19. The method of claim 15, wherein the characteristic is adistance the carriage will travel before a conveyor take-up is full 20.The method of claim 15, further comprising determining if a conveyorbelt is broken based on the rotational direction of the motor and adirection of movement of the carriage being equal.